Welding generator



2 Sheets-Sheet 1 W. J. OESTERLEIN WELDNG GENERATOR Filed June 15, 1.935

INVENTQR.

ATTORNEY.

May 10, 1938.

May 10, 1938. w. J. oEsTERLElN 2,117,035

WELDING GENERATOR Filed June 13, 1955 2 Sheets-Sheet 2 ATTORNEY.

Patented May 10, 1938 UNITED STATES PATENT OFFICE WELDING GENERATORApplication `June 13, 1935, Serial No. 26,354

6 Claims.

This invention relates to electrical generating equipment suitablycontrolled for welding purposes and it comprises an electric generatordriven by an appropriate source of power, which generator iscontrollable in'its outputA through angular adjustment of its commutatorbrushes, said brush adjusting mea-ns being driven by an actuator,including controls therefor for the starting, stopping and reversalthereof, said con- 10 trols being borne by a portable mounting locatableat will at the site of welding, said brush adjusting means further beingengaged cooperatively by the transmitting member of a remote readingposition indicator, the receiving member of which is located in saidportable mounting and at times, if desirable, said portable mounting mayalso bear controls for starting and stopping the `main source of power,and also for reversing the polarity of generator output.

.20 The object of this invention is to provide an arc-welding apparatus,wherein output is varied by shifting of brushes, having a portablecontrol, which may be brought tothe work without the necessity ofmoving' the entire generator and its drive. With the apparatus of thisinvention the operator may stay athis work and nevertheless make suchnecessary changes in brush Setting as the work requires. vFor thispurpose it is necessary that means be provided both for shifting thebrushes and indicating the location thereof. The two necessary andrelated requirements are met in this invention through electrical meansactuatable through an easily portable, ilexible cable. The operator mayconveniently station the portable mounting upon which the control andindicating devices are mounted and proceed with the work of welding,making the necessary adjustments of the generator without leaving thework. y Other improvements and advantages residing in the invention areindicated in the following description of one form of the invention inwhichv phase alternating current supply, although any suitable system ofsupply is contemplated.

The, lines 3 lead to a starting box 5, of standard construction, forstarting and stopping the motor 2. Starting and stopping is accomplishedthrough push-button control, the control power for which is supplied bya transformer 6 through a common supply line 1. During starting the'supply from line 1 is returned through line 8 and a push-button 9 to aground line I 0 and thence through a ground II to the transformer 6.During stopping the control current from supply line 'I returns througha line I2 and a push-button i3 to the ground line I0 and thence throughground II to the transformer 6. The push-buttons 9 and I3 are borne on amounting I4, which is described in detail hereinafter.

The motor 2 through a drive I5 supplies driving energy to the generatorI. The details of the construction of generator I form no part of thisinvention aside from the fact that it is suit- 20 ably wound andconstructed for the supply of arc-welding current and is of the typewherein control is obtained by angular adjustment of the commutatorbrushes. The means for obtaining such angular adjustment may take a wide2 variety of mechanical forms, one form of which is shown in detail inFig. 2.

The output of generator I is supplied to the welding leads I6 interposedin which is a polarity reversing switch I1. The switch I1 is actuated 30by a lever I8 which in turn is shifted by a solenoid core acting betweensolenoids 20 and 2I. Current is supplied to the solenoids 20 and 2|through lead 22 which makes connection with the common supply lead Ifrom' the transformer 6. 5" The return from solenoid 20 is through aline 23 and push-button 24 to the ground return I0 and thence back tothe transformer 6. The return from solenoid 2| in a similar manner isthrough lead 25 and push-button 26, and thence through o ground returnI0 back to the transformer 6. The push-buttons 24 and 26 are borne bythe mounting I4 above referred to. By actuation of pushbuttons 24 or 26the polarity supplied to the welding end 21 of the welding leads I6 canbe reversed at will, and through the actuation of push-buttons 9 and I3the motor 2 and driving generator I may be started or stopped at wilILThe work performed at welding end 21 is by nature variable in characterand requires appropriate current supply for each particular class ofwelding encountered, and to this end the apparatus of this inventionprovides means for varying the output of generator I through theshifting of the angular relationship of the commutator brushes to thegenerator eld.

As shown in Fig. 2, a rotatable brush-bearing ring 28 is mounted to turnin the main generator housings 29 and is controlled in its movement bythe fork 30 which engages pins projecting from a nut 3l mounted upon anadjusting screw 32. The adjusting screw 32 may be manually operated bymeans of a hand-wheel 33, or may be mechanically operated through afriction clutch 36 which is driven by a motor 35 through a reducer 34 sothat independent adjustment by means of the hand-wheel 33 may beaccomplished when desired.

The motor 35, as shown in Fig. 1, is supplied through lines 3l whichlead through a reversingbox 38 to the main supply lines 4. The motor 35is shown diagrammatically and in outline in Fig. 1, the reduction drive34 and the clutch 38 being shown conventionally in Fig. l. The motor 35is indicated as a three-phase motor, but for the purposes of thisinvention any suitable form of motor may be employed, together withappropriate reversing switches.

The reversing-box 38 is actuated for forward movement by a coil 33receiving energizing current through line 48 which extends to thetransformer I5. The return from coil 38 is through line 4l andlimit-switch 42, line 43, push-button 44, and the ground return IIl, andthence through ground II back to the transformer 5. Reversing-box 38 forreturn movement is actuated by a coil 45 which receives energizingcurrent from supply lines 40 in the same manner as coil 33, and thereturn from coil 45 passes through line 43 to limit-switch 41 and thencethrough line 48 to push-button 49, and thence through the ground returnI8 and the ground II to the transformer 6.

When push-button 44 is actuated, coil 39 becomes energized and thereversing-box 38 makes a connection through contacts I] with the leads3l to motor 35, causing the driving of the screw 32 and the shifting tothe left of the fork 38 and consequently the counterclockwise rotationof the brush-holder 28. This movement continues as long as button 44 isdepressed and ceases upon the breaking of the circuit at button 44. Inthe event the operator carelessly prolongs the depression of button 44,the nut 3|, as shown clearly in Fig. 2, engages the foot 5I of thelimitswitch 42, breaking the control circuit and stopping the movementof motor 35. Shifting of the brushes in the opposite direction isaccomplished in exactly similar manner through the depressing ofpush-button 49 and protection against overrunning is provided bylimit-switch 4'I.

Push-buttons 44 and 49 are borne by the mounting I4, which mounting alsocarries a special calibrated galvanometer 52, one terminal of whichmakes connection with the ground return I and thence through ground IIto the transformer B. The other terminal of the galvanometer isconnected through line 53 with a sliding contact 54, shown more indetail in Fig. 2. The sliding contact 54 is carried by and moves withnut 3l and at the same time bears against a slide wire resistance 55, asshown in Fig. 1. The ends of slide wire resistance 55 are continuouslysupplied with current vfrom the transformer 8 through ground return I!)and a lead 56.

The total resistance of element 55 is adjusted to such a value that avery moderate and continuous current is drawn from the transformer 6,such current being suciently small so that no heat dissipating problemarises. For example, if the output of transformer 6 is 110 volts, theresistance of element 55 may suitably be in the neighborhood of 300ohms.

The galvanometer is so wound that when the contact 54 is at the extremeleft zero deflection is indicated and when the contact 54 is at Atheextreme right full scale deflection is shown. The intervening space onthe scale of the galvanometer may be divided in any manner desired, forexample, by stating thereon the nominal output in amperes of thegenerator 2 for each corresponding position of the brush holder 28, itbeing understood that the intermediate deflections of the galvanometercorrespond directly with intermediate stations of the nut 3l.

The mounting I4 may be any suitable small panel with an appropriate baseor casing, preferably compact and light in weight so that it may be of adistinctly portable nature. Connecting with the mounting I4, as shownclearly in Fig. 1, are the lines 8, I2, 43,48, I0, 53, 25, and 23. Theselines are preferably all stranded into one exible cable, the length ofwhich may be arranged so that access to all parts of an average shop maybe had, In certain cases it may not be necessary to include thereversing switch VI1 and the attendant lines 23 and 25, as well as thestarting-box 5, with its attendant lines 8 and I2. In such case themounting I4 will be simplified and will Acarry the galvanometer 52 andthe brush-shifting push-buttons 49 and 44. It is also contemplated thatin c'ases where the generator I is driven by a prime mover, such as aninternal'combustion engine, any suit-able stopping` and startingmechanism therefor may be employed. For example, push-button 9 AmightAserve to close a starter switch, while push-button I3 might serve tointerrupt the ignition system. In like manner, if the generator be ofthe `type wherein the output is controlled through alteration of eldresistance, or through regulation of exciter current, the adjustingscrew 32, and the nut 3l may serve to actuate the variable resistanceinvolved.

'Ihe remote indicating circuit described above is of the potentiometertype, depending for its accuracy upon a relatively constant potentialcurrent supply. For the purpose of this invention ordinary lineregulation is adequate and, as shown in Fig. l, the supply is providedthrough the transformer 6 connected to regular current supply. In case,however, that the generator I is driven by a prime mover, such as aninternal combustion engine, suitable constant potential supply mayordinarily be obtained from the starting battery used to start the primemover. In some cases also where the generator is provided with anexciter, a suitable supply for this purpose may be obtained. It isobvious, however, that any of the various well-known forms of remoteindicating circuits may be employed as the equivalent of the one specicform described above in connection with this invention, and it iscontemplated that any one of such equivalent circuits may be employed.

'Ihe apparatus of this invention has been described above in connectionwith one specific form thereof, but it is intended that the protectionof Letters Patent to be granted hereon be not unnecessarily limitedthereby, but extend Io the full scope of the invention as represented bythe scope of the claims appended hereto.

.l L controllable means also borne by said portable for shifting saidbrushes, a portable mounting carrying'means for stopping, starting, andreversing said motor-driven brush-sluiting means,

mounting for energizing said motcrestopping andstarting means,transmitting means ,for a remote indicating apparatus cooperatively are,ranged with respect to said brushes to be actuated by the shiftingthereof, and receiving means for amd remote position-indicatingapparatus mounted upon said portable mounting.

A2l In an electric generator for electric welding, the combinationcomprising a generator having a ield and brushes angularly shii'tablewith respect thereto, motor-driven means for" shifting said brushes, aportable mounting carrying means for stopping, starting, and reversingsaid mctcr-driven means, an electric-ahy actuated polarity reversingswitch connected to the output of said generator, control means for theactuation of said polarity reversing switch also carried by saidyportable mounting, transmitting means for a remote indicating apparatuscooperatively arranged with respect to said shiftable brushes to beactuated thereby, and receiving means for said remote positionindicating apparatus also mounted upon said portable mounting.

3. In an electric generator for electric Welding, the combinationcomprising a generator having a field and brushes rangularly shii'tablewith respect thereto, a motor for driving said generator, electricallyenergized means for .stopping and starting said motor, a polarityreversing switch connected with the output of said generator,electrically energized means for actuating said polarity reversingswitch, motordriven means for shifting said shiftable brushes, aportable mounting carrying means for stopping, starting, and reversingsaid motor-driven brush-shifting means, control means for saidelectrically energized means for stopping and starting said drivingmotor also carried upon said portable mounting, control means for saidelectrically actuated polarity reversing switch also borne by saidportable mounting, transmitting means for a remote indicating apparatuscooperatively arranged with respect to said shiftable brushes to beactuated thereby, and receiving means for said remote positionindicating apparatus also mounted upon said portable mounting.`

4. In an electric generator for electric Weiding wherein control ofwelding currents is effected by shifting the brushes, the combinationcomprising a housing for said generator, a cir cular shii'table mountingfor said brushes, a screw7 rotatably held withy respect to said housingand tangent thereto, a nut threadedly engaging said screw, meansassociated with said brush, mount ing and cooperatively engaging saidnut, hand means for rotating said screw, and a reversible l motorengaging lsaid screw through a friction drive.

5. In an electric generatorior electric weld-A ing wherein control ofwelding currents is et- .fected by shifting the brunes, the combinationcomprising a housing for said generator, a circular shittable mountingfor said brushes, a screw rotatably held with respect to said housingand tangent thereto, a nut threadedly engaging said screw, meansassociated with said brush mounting and cooperatively engaging said nut,hand means for rotating said screw, a resistance element rigidly fixedwith respect to said housing and parallel with said screw, a slidingcontact carried by said nut and bearing against said resistance element,conductors connectlng the ends of said resistance element with a sourceof electric current o'f constant potential, a conductor connecting oneend of said-"resistance element with the galvanometer, a oonductorconnecting said sliding contact also lwith said (galvanometer, limitswitches engageable by said nut at the extremities of the movementthereof s, reversible motor, a'firiction clutch connecting said motorwith said aforementioned screw, and means for supplying said motor withdriving current through said limit switches.

8. In an electric generator, the combination` comprising ,shiftablemeans for regulating the output of said generator, a reversible motordrivingly connected to said shiftable means and adapted to shift thesame, an electrical positiontransmitting means associated with saidshiftabie means for movement in consonance therea'fiexible cablecarrying control leads connected to said reversible motor for controlthereof and also carrying leads connected to said electrical f with saidposition-transmitting

